Apparatus for the repair of tires



May 27, 1947. E. E. LAKSO APPARATUS FOR THE REPAIR OF TIRES 2 Sheets-Sheet 1 Filed March 28, 1944 R O T N E V m ,Ezjno ELaEso ATTORNEY S May 27, 1947. E. E. LAKSO APPARATUS FOR THE REPAIR OF TIRES Filed March 28, 19 44 2 Sheets-Sheet 2 L R M a mL y m m 7 W m g ATTORNEYS 7 -23 Patented May 27, 1947 APPARATUS FOR THE REPAIR OF TIRES Eino E. Lakso, Fitchburg, Mass, assignor to Clarence W. Vogt, Norwalk, Conn.

Application March 28, 1944, Serial No. 528,396

18 Claims.

This invention relates to apparatus for use in the repair of pneumatic tires by the vulcanizing of uncured rubber or rubber composition at the area on the tire where repair is needed, and to restore the contour and strength of the tire.

In my prior application Serial No. 507,940 I have shown and claimed an apparatus in which the heating effect for the vulcanization is produced by a high frequency current developing an electrostatic field between two electrodes disposed on opposite sides of the tire wall. The electrodes are relatively movable toward and from each other, and spaced from the tire surface by pads of deformable dielectric material so that direct contact of the electrodes with the tire is prevented and proper pressure can be applied uniformly over the area to be vulcanized, and during the vulcanization.

My present invention is an improvement on that illustrated in said application, and has for I one object the provision of a portable device which may receive and support a tire of any size or shape and with any portion thereof needing repair held in convenient position for said repair.

A further object is to provide a more eliective means for positioning and supporting the tire casing to facilitate the application of the electrodes thereto.

A further object is to permit and facilitate the ready adjustment of the electrodes so that the heating eiiect may be produced in any part of the tire wall from near one bead around to near the other bead.

My improved apparatus embodies many novel features of construction and design, and has many advantages and accomplishes many other objects as will be pointed out hereinafter or will be apparent from a consideration of the embodiment shown in the accompanying drawings.

In these drawings:

Fig. 1 is a face view of one form of apparatus embodying my invention.

Fig. 2 is a side view of said apparatus.

Fig. 3 is a view similar to a portion of Fig. 2, but on a larger scale, and with a tire and certain parts of the apparatus shown in section.

Fig. 4 is a section on the line 4-6 of Fig. 3, and taken through the outer electrode support, and

Fig. 5 is a section on the line 55 of Fig. 3, and taken through the inner electrode carrier.

In the construction illustrated, the tire is supported on a portable truck which has a base formed of a pair of angle irons l3 and H, each supported at each end by wheels [2, and connected by rods I 3. This truck base has a tire supporting platform .for holding a tire casing in an inclined position, and preferably at an angle of about to the horizontal. I have illustrated in solid lines a medium' size of tire T on said platform, and in dot and dash lines a larger tire T and a smaller tire T". This platform includes a pair of rods I4 with their lower ends supported by and welded or otherwise rigidly secured to the angle iron I U of the base, and their upper ends secured to a bracket I5. The bracket may be formed of a single casting or of a plurality of members welded or otherwise secured together. This bracket is bolted or otherwise secured to a pair of angle irons I 6 which are supported in the desired inclined position by braces ll having their lower end ecured to the base member H.

The bracket I5 include a pair of socket elements I8 for receivin the upper ends of the rods l4, an arm l9 for adjustably supporting an electrode support, a pair of lugs 2| for attachment of one end of an arcuate track or carrier 22 for a second electrode carrier, and a threaded passage 24 for a tire positioning member 25. The inclined tire platform formed of the rods 14, bracket [5 and angle irons It, carries a second tire positioning member 26.

The apparatus as shown will receive and properly position tires of a wide range of sizes, and the positioning members 25 and 26 are preferably calibrated so that they may be adjusted to the proper position for the tire. The lower part of the tire rests on the lower part of the platform rods l l while the side wall of the upper part rests on the positioning member 26 and has its head engaging the positioning member 25.

The member 26 is in the form of a plate having an arm 2? in sliding engagement with a slot in the bracket 39 and a screw bolt 28 threaded through a bracket 29 and provided with a handle or hand wheel so. By turning the hand wheel the tire support may be raised or lowered to the proper position for the size Of the being repaired. The positioning member 25 is also in the form of a plate or bar and engages the bead of the tire. It is provided with an adjusting screw bolt threaded in the bracket l5 and having a handle or hand wheel 3i and also having a pointer 32 positioned adjacent to the bracket arm [9.

his arm and the arm 27 are calibrated for the various sizes of tires. By size is meant the disstance transversely through the tire, and not the diameter of the tire. For instance, the apparatus shown may take a tire of 6 inches to 14 inches in 3 size, and is shown in the adjusted position for a inch tire. It will be noted that the members and 26 are adjustable in directions at right angles to each other.

The inner electrode support is preferably in the form of a block of wood 28 having an outer surface convexly curved to correspond to the average or mean curvatures of a range of tires to be repaired. That shown is for a 10 inch tire, or a tire somewhat larger or somewhat smaller. The inner surface of the block is concavely curved and rests on a curved hub or flange 33 on the end of the arm i9. This arm projects into the tire between the beads and the hub is so positioned that when the tire is properly adjusted by the members 25 and 28 it will be at the center of the chamber in the tire casing, and inwhi ch the inner tube is held when the tire isin use. The block 29 has an arm 34 rigid or integral there with, and which may be tightly clamped'to the arm lfi by a bolt 35 secured to the arm. at the center of curvature of the hub 33. By loosening the wing nut 36 on said bolt, the blocl; 29 constitutingthe electrode carrier may be rotated on tlie'stationary hub 33 and about the bolt 35 as a centeruntil it is brought into proper registry with a'portion of the tire wall at any place between the bead and the center of the tread andfdepending upon thelocation of the area to be repaired.

The other or outer electrode support is adjustablealong the carrier or track 22, which latter comprises a pair of parallel arcuate rails separately pivoted or hinged at the one end to corresponding brackets 33 secured to the upper ends of the angle irons iii of the inclined tire platform to swing about pintles 45, The arcuate rails 22 are secured together at the other end by a bar H which has an arm 42, the lower end of which is received between the lugs 2| of the bracket le and detachably held by a removable P 1 4 1 The rails are curved in an are having the bolt 35 as a center so that the outer electrode carrier may be adjustedalong the rails so as to come into registry. with thejinner electrode carrier, regardless oftheposition ofethe latter.

The outer electrode carrier includes a carriage having a transverse plateAEjwithfside flanges 46 disposedadjacent to and movable along the rails 22. 'Each'flange has a shoulder ll-resting on the outer edge of its respective rail andhas a pair of spaced studs 43 engaging the inner edge'of its rail. The side walls or flanges 46of'the carriage eaclrha-ve a screw'bolt 49 and a washer or clamping member Silengaging the adjacent rail 22 so that by looseningthe bolt the carriage may be moved along thearcuate rails to the desired position, and'may be tightly clamped in position. I

This outerelectrode support includes a block of wood 5| having a concave inner surface substantially parallel tothe convex surface of the inner electrode support 20. This block has a collar Giswiveled ona bolt 52 which extends radially through the plate of the carriage and threaded 'ina sleeve thereon so that by turninga handle 53 on the outer end of the bolt, the

block may be moved inward radially and toward and fromthe inner electrode carrier, as an ex tension of .theaxis of the bolt 52 intersects an extension of the axis of the bolt 35. The block 5| is detachably secured to the collar 65 on the screw boltf52 by means of screw, bolts 66 or equivalent attaching means.

Secured in any suitable, manner to .the outer surface of the inner carrier block 20 and to the inner surface of the outer carrier block 5i, there are provided spaced curved metal electrode plates 55 and 55. These, as shown particularly in Figs. 1 and 2, may be connected by cables 57 and 58 to a suitable apparatus 59 for generating a high frequency electric current of the proper frequency and voltage to produce an electrostatic field between the two electrodes and to produce a temperature within that field sufficiently high to insure the proper vulcanization of the rubber used in repairing the tire.

The unit 59 per se does not form any novel part of my invention and may be of the same type as commonly employed for producing an electrostatic field by high frequency electric currents. In test operations, a unit designed and intended for diathermy has been found satisfactory, but any other suitable type may be used.

In rder to prevent direct contact of the electrodes with the rubber and to provide proper and uniform pressure over the. opposed. surfaces of the tire wall, which is to be repaired, and in spite ofvariationsin the contour of the outer surface of the tire Wall, and particularly the outer surface at or adjacent to the tread, there are provided a pair of pads. 60 and BI, which lie between the electrodesv and the tire wall. These are formed of suitable dielectric material and are deformable, so that under pressure they will conform to the surfaces of the electrodes and the tire wall and will apply substantially uniform pressru'e across the areato be vulcanized andmaintain the necessary parallelism between the electrodes. Merely as an example, these pads may be formedof canvas and filled with sand. Various other forms of pads andother filling material may be used.

Asthe inner surface of the tire wall has a substantially uniform curvature and the inner block may have the same curvature, the pad 60 may be omitted; but as the outer surface of the tire varies in shape depending upon thetype and designof the tread portion the outer pad 6! is essential for the application of uniform pres sure. and the maintaining of the two electrode platessubstantially parallel.

"Inasmuchas the curvature of the outer and inner surfaces of the tire wall will vary with the size of the tire, it is preferable to provide a plurality of the blocks Hand 51 for different sizes of tires. Because the tire wall is flexible, itis not necessary toprovide separate blocks for each size. For the range of sizes from 6 inches to 14 inches, three or four different pairs of blocks may be used, each pair with a different curvature and each suitablefor tWo or more sizes of tires. The innerblock may be readily removed bytaking'off. the wing nut 36 and a diiferent size substituted, and the outer block maybe similarly replaced by a different size by-removing the wing nuts on the bolts 66. A separateelectrode plate may be fixed to each block and-removed with it, or the electrodepla tes may be flexible and affixed to the cables 50 that they need not be removed and will takethecurvature of any block being .used

In the useof, the apparatus above described, the pin 43 may beremoved and the arcuate rails 22 with the outer electrode carrier mounted thereon may be swung about the pivot bolt 40 to the position shownindotted lines in Fig. 2. The size of the tire to be repaired is noted and the hand wheels 30 and}! turned to bring the tire. positioning members 25' an'd 26 to the proper position for that particular size of tire. If necessary, the blocks 20 and 5|, with or without the electrodes, may be removed and replaced by a different size, corresponding to that of the tire.

To position a tire, the tire positioners 25 and 26 are set to a size slightly smaller than the tire to be vulcanized. Then the inner electrode block 20 is placed into position, being inserted into the tire carcass at another point along the tire periphery which has been spread open by a conventional spreader. The tire positioners are now adjusted to the proper tire size which brings the inner surface of the tire into contact with the inner electrode pad 60 or into contact with the curved electrode plate 55 if the pad 60 be omitted. The arcuate rail member 22 is swung into the position shown in Fig. 3 and locked by pin 43. The outer electrode carrier is then brought into position opposite the inner electrode and secured by means of clamps '50 and screw 49. The pad 6| is placed between the outer surface of the tire and the inner surface of the block 5! and pressure is then applied by means of screw 52 and lever 53.

If the curvature of the inner surface of the tire wall does not exactly conform to the curvature of the inner electrode 55 and the substantially parallel outer electrode 55, the pressure applied in moving the outer electrode toward the inner one will act to slightly bend the tire wall so that all parts of the wall between the electrodes will be subjected to the desired pressure.

With the parts in position and the tire wall under the desired pressure, the current is turned on to produce the electrostatic heating field to vulcanize the rubber applied in repairing the tire.

It will be obvious that if the apparatus is designed for the repair of only a single size of tire, or a limited range of sizes, the means for adjusting the positions of the tire supporting elements 25 and 25 may be omitted and these parts made rigid with the inclined platform. Suitable means is preferably employed for shutting off the current when the vulcanization has been completed. This may be of the automatic type shown and claimed in application Serial No. 514,452 or that shown and claimed in application Serial No. 536,068.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

1. An apparatus for repairing tires, including an inclined platform for supporting the tire, a pair of electrodes for clamping a portion of the tire wall therebetween, and means positioned at one end of the platform and adapted to contact with the tire for raising and lowering a portion of the tire to vary the inclination thereof in respect to the platform and in respect to said electrodes.

2. An apparatus for repairing tires, including an inclined platform for supporting the tire, a pair of electrodes for clamping a portion of the tire wall therebetween, and means connected with said platform and adapted to contact with the tire, for sliding the tire along the platform and in respect to said electrodes.

3. An apparatus for repairing tires, including a platform for supporting the tire, an arm carried thereby and having an electrode for positioning within the tire, and means connected with said platform and adapted to contact with the tire, for moving the tire bodily in respect to the electrode.

4. An apparatus for repairing tires including a 6 platform for supporting the tire, an arm carried by said platform and having an electrode pivotally secured thereto to swing in an are along the inner surface of the tire wall, and means connected with said platform and adapted to contact with the tire, for moving a wall of the tire toward and from the pivotal center of said electrode.

5. An apparatus for repairing tires, including a pair of wooden blocks constituting electrode plate carriers, one of said blocks presenting a concave surface and the other a convex surface, metal electrode plates substantially conforming to said surfaces, a pair of pads of deformable dielectric material, and means for clamping a tire between said pads with said electrodes upon the outer surfaces of said pads.

6. An apparatus for repairing tires including an arm adapted to extend substantially radially of the tire, an electrode plate carrier secured to the end of said arm and presenting a convex outer surface, means for supporting a tire and adjusting the position thereof to bring the inner surface of the tire wall substantially concentric with said surface, a second electrode plate carrier having a concave surface substantially parallel to the surface of the first mentioned carrier, curved electrode plates carried by said concave and convex surfaces respectively, and a pair of deformable bags of dielectric material positioned in engagement with and between said electrode plates and between which bags a tire wall may be clamped.

7. An apparatus for the repair of tires, including a tire support, a pair of curved electrode plates, means for producing a high frequency electrostatic field between said electrodes, a pivoted support for holding one electrode plate within the tire, an arcuate member concentric with the pivotal center of said support, a support for the other electrode plate movable along said arcuate member and into opposed relationship to the electrode carried by said pivoted support, and an adjustable member connected to said support and adapted to contact with the tire, to position a wall of the tire in selected position in respect to the pivotal center of said second mentioned support.

8. An apparatus for the repair of tires, including a tire support, a pair of curved electrode plates, means for producing a high frequency electrostatic field between said electrode plates, a pivoted support for holding one electrode plate within the tire, an arcuate member concentric with the pivotal center of said support, a support for the other electrode plate movable along said arcuate member and into opposed relationship to the electrode plate carried by said pivoted support, a member connected to said tire support, adjustable in respect thereto, and adapted to contact with the tire for holding a wall of the tire in selected position in respect to the said pivoted support, and means for adjusting the second mentioned electrode plate toward and from said pivotal center, whereby the tire wall may be clamped between said electrode plates.

9. An apparatus for the repair of tires, including a tire support, a pair of curved electrode plates, means for producing a high frequency electrostatic field between said electrodes, a pivoted support for holding one electrode plate within the tire, an arcuate member concentric with the pivotal center of said support, a support for the other electrode plate movable along said arcuate member and into opposed relationship to the electrode plate carried by said pivoted support, and means adapted to contact with thetire and movable in respect .to said tire support, for adjusting attire in the directionof its axis andin a direction at rightangles to its axis to positiona.

tire wall concentric with said members and therebetween.

10, Anapparatus for the repair of tires, including a pair of curved electrode plates, means for producing a high frequency electrostatic field between saidelectrode plates, a pivoted support for holding one electrode plate within the tire, an arcuate member concentric with the pivotal center of saidsupport, a support for theother electrode plates movable along said arcuate member andinto opposedrelationship. to the electrode plate carried by said pivoted support, avdeformable bag: adapted'to rest on the tire and beneath said. second mentioned electrode plate, means adaptedto support the weight of the tire independently of either of said electrode supports, and means for adjusting the position of the tire in respect to said electrode supports.

11. An apparatus for repairing tires including a pair. of electrode plates spaced to receive the tire wall therebetween and independently adjustable along the tire wall and toward and from the tire bead, and means for supporting and positioning. the tire independent of said electrode plates and including a member for engaging the innercircumferenceof the tirebeadfor moving the tire substantially in its own plane and a member for engaging the outer surface of the outer wall for adjusting the tire in a direction substantially parallel toits axis.

12;. An apparatus for repairing tires including a pair of substantially parallel electrode plates spaced to receive the tire wall therebetween and independently adjustable along the tire wall and toward and from the tire bead, while maintaining said electrode plates substantially parallel, means for producing a high frequency electrostatic field between said electrode plates, a member for engaging the outersurface of'the tire wall, a memher for engaging the edge of the tire bead and means for operating said members independently ofgeach other to position the tire in respect to said electrode plates.

13; An apparatus for repairing tires, including a platform having an arm rigid therewith, an electrode carrier pivotally secured to the end of said'arm, a track secured to said platform and extending in an are substantially concentric with the-pivotal center of said electrode carrier, a second electrode carrier slidably supported on said track for adjustingmovementtherealong into selected position, amember adapted to contact with the tire for adjustably moving and for holding the tire in a=predetermined position in respect to the platform and said electrode carriers, electrodes on said carriers respectively, andjmeans for applying a high frequency electric potential between said electrodes.

14 An apparatus for repairing tires,.including a platform having an arm rigid therewith, an electrode carrier pivotally secured to the end of said arm. a track secured to said platform. and extending in anarc substantially concentric with the-pivotal center of-said'electrode carrier, a second electrodecarrier slidably supported on said trackfor adjustingmovement therealonginto selected position, means for adjusting saidfsecondmentioned electrode carrier toward .and fromthe first-mentioned one'and radially in respect to'the pivotal center'of the latter, a;member adjustable inrespect tosaid. platform; and adaptedito. contact with thetire for adjustablymoving and holdingthe tire in selectedposition in respectto said electrode carriers, electrodes on said carriers respectively, and means for applying ahigh frequency electric potential to said electrodes.

15. In an apparatus for conditioning tires, the combination comprising a pair of electrodes, means supporting said electrodes with respective surfaces in spacedzsubstantially parallel opposed relationship, means independent of said electrode supporting means for supporting and holding a tire with the tire section to be conditioned between saidsurfaces, means for guiding said electrodes for adjusting movement edgewise of their surfaces relative to said tire supporting means, whereby. said electrode surfaces can be adjusted relatively with respect. to and along a tire wall, while maintaining said electrode surfaces substantially parallel, a pair of members of dielectric material between said electrodes for pressing the tire section to be conditioned therebetween, said latter members having respective'surfaces on one side conformablyengaging substantially said electrode surfaces respectively, and having respective surfaces onanother side'contoured to conformably engage substantially the opposite surfaces respeetively of the tire section to be conditioned, scans for moving said electrodes relatively towards oraway from each other while maintaining said electrode surfaces parallel, and means for ap plying a high frequency electrical potential to said electrodes.

16. In anapparatus for conditioning tires, the combination comprising a pair of spaced electrodes adapted to extend on opposite sides of the the section to be conditioned and .presentingsubstantially parallel respective opposed surfaces, means for supporting one of said electrodes for adjusting movement edgewise of its surface, means supporting the other electrode for adjusting movement edgewise of its surface, Whereby said surfaces are maintained substantially parallel in adjusted position of. said electrodes, means for .supportingone of said electrodes for adjusting'movement in either direction substantially normal to its surface, a pair of members of dielectric material between said electrodes for pressing a tire Wall therebetween having respective surfaces on one side conformably engaging substantially said electrode surfaces respectively and having respective opposed surfaces on another side contoured to conformably engage substantially opposite surfaces respectively of the tire section to be conditioned, and meansfor applying a high frequency electrical potential to said electrodes.

17. In an apparatus for conditioningtires, the combination comprising. a pair of opposed electrodes adapted to extend on opposite sides of the tiresection to be conditioned, and presenting curved opposed concentric respective surfaces, means for supporting one of said electrodes for angular-adjusting.movement about the center of its curved surface, means for supporting the other electrode for'angular adjusting movement about said center and for movement radially of said center, a pairof pressure applying members of dielectric material between said electrodes hav ingrespective surfaces onone side conformably engagingv substantially said electrode surfaces respectively and'having respective opposed surfaces on another side contoured to conformably engage substantially opposite surfaces respectively of thetiresection to: be conditioned, and means for applying a high frequency electrical potential to said electrodes.

18. In an apparatus for conditioning tires, the combination comprising a platform, a first block of insulating material supported on said platform, a first electrode plate secured to said block and presenting an upwardly facing surface, an electrode support secured to said platform, a second block of insulating material mounted on said support above said platform and said first block, a second electrode plate secured to said second block above said first electrode plate and presentinga downwardly facing surface substantially parallel and opposite to said upwardly facing electrode surface, the section of the tire to be conditioned being adapted to be supported between said electrode plates, a first pressure applying member of dielectric material having one side conformably engaging substantially the upwardly facing surface of said first electrode plate and having its opposite side contoured for substantial conforming engagement substantially with the adjacent surface of the tire section to be conditioned, a second pressure applying member of dielectric material having one side conformably engaging substantially the downwardly facing surface of said second electrode plate and having its opposite side contoured for substantial conforming engagement substantially with the other adjacent surface of the tire section to be conditioned, an adjusting screw mounted on said electrode support for moving the second block substantially normally of said electrode surfaces, and means for applying a high frequency electric potential to said electrode plates.

ElNO E. LAKSO.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

